Crab pot

ABSTRACT

A crab pot having improved yield. A traditional commercial crab pot comprises a trigger structure that rotates between open and closed positions. The crabs enter the trap by pushing trigger members inwardly as the crabs pass through a trap opening. The trigger members are prevented from swinging outwardly, so crabs should not be able to leave through the trap opening. To bias the trigger structure into the closed position, the trigger structure comprises a counterweight member that biases the trigger members into a position where they span the trap opening and prevent egress of crabs. A protection structure is provided which prevents crabs from interfering with the operation of the trigger structure. The protection structure prevents the crabs from interfering either with the portions of the trigger members which extend below the trap opening and/or the counterweight member located above the trap opening. The protection structure thus may take the form of either a stirrup structure which receives the bottom ends of the trigger members or a hood which extends over and protects the counterweight member. The stirrup structure and the hood structure do not interfere with normal operation of the trigger structure. Preferably, both a hood structure and a stirrup structure are used at the same time.

TECHNICAL FIELD

The present invention relates to pots for trapping crabs and the likeand, more particularly, to crab pots having gated openings that allowingress but not egress of the crabs.

1. Background of the Invention

Crabs are commercially harvested by placing crab pots in areas wherecrabs are present. Bait that is attractive to crabs is placed in thesecrab pots and crabs enter the pots in search of the bait. The crab potsare enclosure-type trapping devices that crabs may enter but, in theory,cannot leave.

During use, the pots are tied to a buoy using a line. The buoy floatsabove the pot to mark the location of the pot. After a suitable periodof time has passed, the crabber locates the pot using the buoy and liftsthe pot using the line.

As crab pots are immersed in salt water and submitted to fairly extremeconditions during use, their design has been kept fairly simple andrugged. The basic design of a crab pot has remained unchanged for manydecades.

2. Prior Art

A professional patentability search conducted on behalf of the applicantuncovered the following references: U.S. Pat. No. 5,259,809 issued Nov.9, 1993, to Rainey, Jr.; Danish Pat. No. 22294; U.S. Pat. No. 2,716,304issued Aug. 30, 1955 to Taylor; and U.S. Pat. No. 3,440,758 issued Apr.29, 1969 to Prince.

Of the foregoing references, the patents to Taylor and Prince relate totrapping devices specifically adapted to trap crabs. The Rainey, Jr.patent discloses a trapping device adapted to trap shrimp. The Danishpatent appears to show a trapping device similar in overall structure tothe other devices but, to the applicant's knowledge, does not relate tocrabs.

OBJECTS OF THE INVENTION

From the foregoing, it should be clear that one primary object of theinvention is to provide improved methods and devices for trapping crabs.

Another more specific object of the present invention is to obtainmethods and apparatus for trapping crabs that exhibit a favorable mix ofthe following characteristics:

(a) reduces the likelihood that legal size crabs, once within the pot,will escape from the pot;

(b) reduces the likelihood that crabs within the pot will block entry ofother crabs into the pot;

(c) reduces the likelihood that trigger wires of the pot will be stuckin the open position;

(d) reduces the likelihood that foreign materials will open the triggerwires;

(e) can be retrofitted to existing pots to improve the ability of theseexisting pots to catch crabs;

(f) allow the weight of the counterbalance attached to the trigger wiresto be increased;

(g) reduces the likelihood that the trigger wires will be damaged; and

(h) can be easily and inexpensively manufactured and installed.

SUMMARY OF THE INVENTION

These and other objects are obtained by the present invention, whichbasically comprises a crab trap in which one or more protectionstructures are located within the trap to prevent crabs from interferingwith or opening a trigger structure employed to allow ingress but notegress of crabs into the pot.

In particular, commercial crab traps often employ a trigger structurethat comprises two trigger members that extend across a trap opening anda counterweight member which is connected to the trigger members in away that forces these trigger members into a closed position in whichthey span the trap opening.

An implicit assumption in the design of crab pots is that because crabshave no intelligence per se, they will not figure out how to open thetrigger structure once they are inside the trap. This assumption may begenerally valid, but it does not take into account the fact that thecrabs may accidentally move around inside the trap in a manner thatresults in the trigger structure being placed in its open position. Atthis point, either the crab who has accidentally opened the triggerstructure may escape or other crabs nearby may escape.

Additionally, while a crab may not open the trigger structure, the crabmay interfere with its operation such that the trigger structure is keptin a closed position that does not allow the entry of any additionalcrabs. While a crab pot usually has two and sometimes four openings, thecrab cannot be expected to find the other opening if one is blocked.This is particularly true because crabs tend to move in the direction ofcurrents; if the crab is frustrated from entering one opening of thetrap, it may simply move past the trap until it can no longer detect thebait.

The protection structures of the present invention are arranged in oneor preferably two places within the crab pot to prevent crabs fromaccidentally interfering with the operation of the trigger structure.First, a hood structure may be placed over the counterweight portion ofthis trigger structure in order to prevent crabs from interfering withthe movement of this trigger structure. In particular, a crab may sit ontop of the trigger structure, which would prevent the trigger structurefrom being moved into its open position, and thus prevent crabs fromentering the pot. Additionally, it may be possible for a crab movingaround within the trap to grip the counterweight portion in a mannerthat raises the trigger members. If the crab grips the counterweightportion and then stops moving, the trigger structure may be placed inits open position, allowing the other crabs within the pot to escape.

The hood structure thus comprises a piece of rigid or semi-rigidmaterial that is placed over the counterweight member in a manner thatsignificantly reduces the likelihood that a crab will interfere with themovement of this counterweight member.

Second, a stirrup structure may be provided to protect the bottom endsof the trigger members. Normally, these members extend past the openingand down into the trap itself. A crab moving radially inwardly withinthe trap may hook these ends on its shell in a manner that causes thetrigger structure to move into the open position. At this point, thatcrab may be able to exit through the trap opening, or another crabnearby may also be able to exit through the trap opening.

The stirrup structure comprises a pair of cup-like stirrups that areconfigured to define channels that receive the ends of the triggerwires. These stirrups allow crabs passing into the pot through the trapopening to displace the trigger members to place the trigger structureinto the open position; however, the stirrups prevent a crab within thetrap from moving in the same direction and accidentally opening thetrigger structure from below.

Additionally, the trigger structure is relatively loosely arrangedwithin the pot. It can be slid side-to-side a short distance at itsupper end, and the lower end of the trigger members can be displaced tothe side by approximately one inch. Accordingly, a crab pressing againstthese trigger members and arranged at an angle to the trap opening canpossibly squeeze out of the opening past the trigger members. The hoodstructure and the stirrup structure both can be arranged to prevent thissideways movement of the trigger members. Accordingly, legal size crabsare much less likely to squeeze back out of the trap opening by slidingthe trigger members sideways.

Ideally, both a hood structure and a trigger structure will be used inone trap.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art crab pot in which mesh framematerial has been partially removed for clarity of illustration;

FIGS. 2 and 3 are side section views of the crab pot shown in FIG. 1depicting certain problems associated with the operation of such a crabpot;

FIG. 4 is a top view of a crab pot employing the principles of thepresent invention;

FIG. 5 is a perspective view of one trap opening of the crab potdepicted in FIG. 4 showing details of the operation of the presentinvention;

FIGS. 6 and 7 are side partial cut-away views taken along lines 7--7 inFIG. 4 which show the operation of the present invention under differentpossible circumstances;

FIG. 8 is a side partial cut-away view showing the present invention ina slightly different form;

FIG. 9 is an interior view showing the present invention as depicted inFIG. 8; and

FIG. 10 is a perspective view showing details of operation of thepresent invention as shown in FIGS. 8 and 9.

DETAILED DESCRIPTION OF THE INVENTION

Referring initially to FIGS. 1, 2, and 3 of the drawing, an exemplaryprior art crab pot 10 will initially be described. The present inventionwill be described with reference to FIGS. 4-10 after the introductorydiscussion of the prior art.

Formed in the pot 10 are funnels 12 and 14. An interior of the pot 10 isindicated by reference character 16, while an exterior thereof isidentified by reference character 18. The conventional crab pot 10basically comprises a frame portion 20, frame material 22 which isarranged on the frame (partly shown in FIG. 1 for clarity), openings 24and 26, and a trigger structure 28 that allows crabs to enter the pot 10through the opening 26 but is designed to prevent crabs from exiting thepot 10 through the opening 26.

The construction, operation, and use of the crab pot 10 is well known inthe art and will not be described in detail herein. However, severalaspects of the prior art trap 10 will be described in further detail tohelp the reader understand the construction, operation, and use of thepresent invention.

In particular, the frame 20 comprises an opening structure 30 whichdefines the trap opening 26. The opening structure 30 is basicallyrectangular in shape, being shorter in height than it is in width.

The trigger structure 28 is formed from a single piece of rigid wire 32that is wrapped around the opening structure 30 to define first andsecond trigger members 34 and 36 and a counterweight member 38. Moreparticularly, the wire 32 is wrapped around the opening structure 30 ata loop 40 located between the first trigger member 34 and thecounterweight member 38. The trigger wire 32 is also wrapped around theopening structure 30 at a loop 42 arranged between the counterweightstructure 38 and the second trigger member 36.

This arrangement is shown in greater detail in FIGS. 2 and 3. ComparingFIGS. 2, and 3, it can be seen that the trigger structure 28 configuredas described can rotate between a closed position (FIG. 2) and an openposition (FIG. 3) about a rotation axis 44 defined by an upper portion46 of the opening structure 30. Additionally, it can be seen that thecounterweight member 38 inwardly extends at an angle relative tovertical; this allows gravity to act on the trigger members 34 and 36and the counterweight 38 to bias the trigger structure 28 into theclosed position shown in FIG. 2.

Referring now for a moment more particularly to FIG. 2, schematicallydepicted therein at 48 is a crab that is resting on the counterbalancemember 38. If the crab 48 should sit in this position, it couldinterfere with movement of the counterweight member 38 and prevent acrab from passing through the trap opening 26 into the interior of thetrap 10. The possibility that the crab 48 will be able to prevent entryof additional crabs is enhanced by the affect of gravity on the triggerstructure 28 and the fact that the length of the counterweight member 38provides leverage that assists the crab 48 in holding the triggerstructure 28 in the closed position. Clearly, if the situation depictedin FIG. 2 should occur, crabs may not be able to enter the pot 10through the trap opening 26.

FIG. 3 depicts another situation which may very well occur with a numberof crabs moving around within the pot 10. A crab within the pot 10 maymove in a radially inward direction indicated by arrow 48 in FIG. 3. Inso doing, the shell of the crab 46 may catch a lower end 50 of thetrigger member 36 in a manner that causes the trigger structure 28 torotate into the open position as shown. In this open position, the crab46 itself may escape through the trap opening 26 or another crab withinthe trap 10 may pass through the opening 26.

It should be noted that the situations depicted in FIGS. 2 and 3 are,perhaps contrary to expectations, quite likely to happen. The crabs arevery mobile and agile in their environment. Even within the trap, theywill tend to roam around before ultimately settling in one position.Additionally, when pulled, a trap may contain as many as 20 or 30 crabs.As the number of crabs within the trap increases, the likelihood thatone or more of these crabs will interfere with the operation of thetrigger structure 28 also increases.

Referring now to FIG. 4, depicted at 110 therein is a crab potconstructed in accordance with, and embodying, the principles of thepresent invention. In FIG. 4, the frame material forming a part thereofthe crab pot 110 is not shown to provide a clearer picture of theoperation and construction of the present invention. It should be clear,however, that such frame material would be required to obtain afunctioning crab pot.

Additionally, the crab pot 110 is shown with four trap openings 112,114, 116, and 118 rather than with two openings as in the prior art pot10 described above. Given that four such openings are employed in thepot 110, the funnels 120, 122, 124, and 126 associated therewith aremade significantly shallower than those of the prior art crab pot 110.

The principles of the present invention are, however, equally applicableto the prior art crab pot 10 described above. The pot 110 comprises aframe 128 having a perimeter structure 130 and opening structures 132,134, 136, and 138 associated with each of the trap openings 112, 114,116, and 118, respectively. Each of the opening structures 132-138 arespaced radially inwardly towards a center axis A of the crab pot 110.Brace structures 140, 142, 144, and 146 maintain the opening structures132-138 in the appropriate position. Referring only to the bracestructure 140 for the purposes of clarity, it can be seen than each ofthese brace structures 140-146 comprises a first brace member 148 and asecond brace member 150 which extend between the perimeter structure 130and the opening structure 132.

Arranged adjacent to each of the trap openings 112-118 is a stirrupstructure identified by reference characters 152, 154, 156, and 158.Also associated with each of these trap openings 112-118 is a hoodstructure, although only one such hood structure 160, associated withthe trap opening 112, is shown in FIG. 4 for purposes of clarity.

Referring now to FIG. 5, the stirrup structure 152 and hood structure160 associated with the trap opening 112 are shown in further detail.FIG. 3 also shows that the perimeter structure 130 comprises upper andlower ring members 162 and 164 and first and second vertical spacingmembers 166 and 168.

From FIG. 3, it can be seen that the brace members 148 and 150 of thebrace structure 140 extend between the vertical spacing member 166 andthe opening structure 132 and the spacing member 168 and the structure132, respectively. FIG. 3 additionally shows frame material 170 thatextends between the peripheral structure 130 and the opening structure132 to define the funnel 120.

Referring initially to the stirrup structure 152, the exemplarystructure 152 comprises first and second stirrup members 172 and 174.These stirrup members 172 and 174 are essentially identical and only thestructure 172 will be described herein in detail.

The stirrup member 172 comprises a single piece of rigid wire in aU-shaped configuration, with upper ends 176 and 178 bent backwards suchthat they extend generally orthogonally from the plane of the U. Theseends 176 and 178 are securely attached to a bottom portion 180 of theopening structure 132 such that a channel defining portion 180 of thestirrup member 172 is arranged in a substantially vernical plane andspaced radially inwardly from the opening structure 132 towards the axisA. A similar channel defining portion 182 is formed by the stirrupmember 174.

The pot 110 comprises a trigger structure 183 for allowing crabs toenter, but preventing crabs from leaving, the pot 110. The triggerstructure 183 comprises trigger members 184 and 186 that span the trapopening 112 in a manner the same as the trigger members 34 and 36 of theprior art crab pot 10. The trigger members 184 and 186 rotate about arotation axis defined by an upper portion 187 of the opening structure132. Lower ends 188 and 190 of these trigger members 184 and 186 extendbelow the lower portion 180 of the opening structure 132.

Additionally, the stirrup members 172 and 174 are spaced along theopening structure lower portion 180 such that, under normal conditions,the lower ends 188 and 190 of the trigger members 184 and 186 enter intochannels 192 and 194 defined by the channel defining portions 180 and182 of these stirrup members 172 and 174. These channels 192 and 194 aregenerally parallel to each other and extend along lines extendinggenerally radially outwardly from the center axis A of the pot 110.

The stirrup structure 152 solves certain of the problems identifiedabove in reference to the prior art crab pot 10. Initially, as shown inFIG. 8, the stirrup member 172 will prevent a crab 196 located under thefunnel 120 from moving radially inwardly towards the center axis Aagainst the lower end 188 of the trigger member 184. The stirrup member172 thus prevents the crab 196 from opening the trigger structure 183formed by the trigger members 184 and 186.

Further, the stirrup members 172 and 174 act on the lower ends 188 and190 of the trigger members 184 and 186 to prevent these members from thepushed from side-to-side along the bottom portion 180 of the openingstructure 132. By preventing the spread or sideways movement of thesetrigger members 184 and 186, the stirrup members 172 and 174 preventcrabs from escaping simply by exhibiting a lateral force on the triggermember lower ends 188 and 190.

Referring now to the hood structure 160, it can be seen from FIGS. 3 and7 that this structure 160 engages the upper portion 187 of the openingstructure 130 and is attached by stainless wire 200 to the framematerial 170 defining the funnel 120.

As shown perhaps best in FIGS. 7 and 8, the hood structure defines aninterior chamber 202 in which a counterbalance member 204 of the triggerstructure 130 is contained.

The exact shape and dimensions of the hood structure 160 are notcritical as long as the chamber 202 defined thereby allows the triggerstructure to rotate between closed (solid lines) and open (broken lines)positions as shown in FIG. 7. The applicant has determined that a cavity202 generally in the shape of a triangular extrusion (see FIGS. 6 and 7)is suitable for this purpose because it allows the required motion ofthe trigger structure 183 while providing convenient connections to theopening structure upper portion 187 and funnel 120.

The hood structure 160 prevents crabs from interfering with theoperation of the counterbalance member 204 of the trigger structure 183.For example, as shown in FIG. 7, a crab 206 that climbed on top of thefunnel 120 would simply rest on an upper surface 208 of the hoodstructure 160 and would not interfere with the movement of the triggerstructure 183. Additionally, end walls 210 (FIG. 7) and 212 (FIG. 3) andan inner wall 214 prevent a crab from reaching underneath the upper wall208 to interfere with the operation of the trigger structure 183.

For ease of manufacturing, the exemplary hood structure 160 does notcomprise an outer wall opposing the upper and inner walls 208 and 214;instead, the hood structure 160 relies on the frame material 170 formingan upper portion 216 of the funnel 120 to protect the cavity 202. Whilethe frame material 170 will not provide the same degree of protection asthe hood structure 160, the chances are much lower that a crab on theoutside of the pot 110 will interfere with the operation of the triggerstructure 183 because the concentration of crabs outside the pot 110will be much lower than that inside the pot 110.

The exemplary hood structure 160 is a single piece made out of injectionmolded plastic. However, clearly other materials that are resistant tothe corrosive affects of salt water may be used. These materials includewood, grounded stainless steel, steel.

Additionally, a plurality of holes 220 are formed in the upper surface208; these holes 220 allow the stainless wire 200 to be placed at anappropriate location to secure the hood structure 160 to the framematerial 170. Similarly, notches 222 (only one shown in FIG. 3) areformed in lower portions 224 and 226 of the side walls 210 and 212.These notches 222 are sized, dimensioned, and located to engage theupper portion 187 of the opening structure 132. These notches 222positively engage the upper portion 187 such that a substantial amountof force is required to remove the hood structure 160 from the openingstructure 132. Therefore, while the notches 222 allow the hood structure160 to be removed if desired, these notches 222 engage the openingstructure upper portion 187 in a manner that prevents the hood structure160 inadvertently knocked off or removed from the upper portion 187.

Referring now for a moment to FIG. 11, the hood structure 160 isdepicted therein from the perspective of the center axis A of the pot110 looking out through the trap opening 112. In FIG. 11, the side walls210 and 212 of the hood structure 160 and the counterweight member 204of the trigger structure 183 are shown in broken lines. FIG. 11 alsoshows that the trigger structure 183 further comprises loop portions 226and 228. The loop portion 226 is located between the first triggermember 184 and the counterweight member 204, while the second loopportion 228 is located between the counterweight member 204 and thesecond trigger member 186.

In this context, it can be seen that the trigger structure 183 is formedfrom a single piece of wire and that the loop portions 226 and 228extend around the upper portion 187 of the opening structure 132.Therefore, referring now for a moment to FIGS. 7, 8, and 10, it can beseen that gravity will act on the counterbalance member 204 and triggermember 184 to hold the trigger structure 183 in its closed position.However, without the hood structure 60, only the frame material 170keeps the entire trigger structure 183 from moving along the openingstructure upper portion 187. Since the frame material 170 comprisesfairly significant open spaces and is somewhat flexible, without thehood structure 160 the entire trigger structure 183 can move for up toan inch along the upper portion 187 of the opening structure 132.

However, as shown in FIG. 11, the side walls 210 and 212 of the hoodstructure 160 are spaced immediately adjacent to the loop portions 226and 228 of the trigger structure 183. Friction between the notches 222and the upper portion 187 hold the hood structure 160 onto the openingstructure upper portion 187. This friction inhibits movement of the hoodstructure 160 and therefore the trigger structure 183 along the rotationaxis defined by the upper portion 187. This movement is furtherrestricted by the fact that the hood structure 160 is attached to thefunnel 120 by the stainless wires 200. The hood structure 160 thussubstantially reduces the likelihood that a crab will create a largeenough opening to walk through by applying a force to one of the triggermembers 184 and 186 that moves the entire trigger structure to one side.

Referring now to FIGS. 8, 9, and 10, yet another exemplary stirrupstructure 310 is depicted therein. This stirrup structure 310 operatesin the same basic manner as the stirrup structure 152 described above,but is made out of injection molded plastic rather than rigid wire.

The stirrup structure 310 basically comprises first and second stirrupmembers 312 and 314, and a fastening plate 316. As shown in FIG. 9, thestirrup members 312 and 314 have a generally U-shaped configuration whenlooking from inside the trap. The trigger members 184 and 186 arereceived in channels 318 and 320 formed by the stirrup members 312 and314. These channels 318 and 320 allow free movement of the triggermembers 184 and 186 as the trigger structure 183 moves between theopened and closed positions.

The stirrup members 312 and 314 are the same, and only one of these willbe explained below with the understanding that this explanation appliesto the other.

The stirrup structure 312 comprises a bottom wall 322 and side walls 324and 326. The channel 318 is defined by these walls 322, 324, and 326.Formed at the upper portion of the side walls 324 and 326 are attachmentmembers 328 and 330. Grooves 332 and 334 are formed by the attachmentmembers 328 and 330. These grooves 332 and 334 are sized and dimensionedto create a positive engagement with the lower portion 180 of theopening structure 132.

The fastening plate 316 is attached to both of the stirrup members 312and 314 such that these channels 318 and 320 defined by the structures312 and 314 are spaced from each other the same distance as that betweenthe trigger members 184 and 186. Additionally, a plurality of holes 336are formed in the attachment plate 316.

In operation, the notches in the attachment members engage the lowerportion 180 of the opening structure 132 and stainless wire is employedto attach the attachment plate 316 to a lower portion 340 of the funnel120. Properly installed, the stirrup structure 310 is mounted such thatthe trigger members 184 and 186 are received in the channels 318 and320. The trigger structure 183 operates normally, but interference withthe motion thereof by crabs underneath the funnel 120 is substantiallyeliminated.

The stirrup structure 310 is particularly adapted to be injected moldedout of plastic, although other materials that are resistant to corrosionin a marine environment may be used.

With either the hood structure 160 or the stirrup structure 310, theexact shape of the structure is not important, as long as it can: (a) besecurely attached to the opening structure 132 and funnel 120; (b) doesnot interfere with the normal movement of the trigger structure 183; and(c) prevents crabs within the pot 110 from interfering with normaloperation of the trigger structure 183.

It should also be clear that the hood structure 168 and stirrupstructures 158 and 310 may be arranged on a conventional crab pot suchas that shown at 10 in FIGS. 1-3. Additionally, these structures 160,158, and 310 may be installed on the pot at the factory, or may also beshipped in a retrofit kit for existing pots.

It should be clear from the foregoing that the present invention may beembodied in other specific forms without departing from the essentialcharacteristics thereof. The present embodiments are therefore to beconsidered in all respects as illustrative and not restrictive, thescope of the invention being indicated by the appended claims ratherthan by the foregoing description; all changes which come within themeaning and range of equivalency of the claims are therefore intended tobe embraced therein.

I claim:
 1. An apparatus for trapping crabs, comprising:a framecomprising a peripheral structure; frame material arranged on the frameto define an interior chamber, the frame material being adapted toprevent passage of crabs therethrough; at least one trap opening in theframe material through which crabs may pass; a trigger structurearranged to rotate about a rotation axis between a closed position andan open position, where the trigger structure prevents passage of crabsfrom the interior chamber through the trap opening when in the closedposition and allows passage of crabs through the trap opening when inthe open position, the trigger structure having a first portion arrangedto span the trap opening when the trigger structure is in the closedposition and a second portion that acts on the first portion to bias thetrigger structure into the closed position; and hood means for extendingover the second portion of the trigger structure to inhibit the abilityof crabs to interfere with movement of the second portion of the triggerstructure.
 2. An apparatus as recited in claim 1, in which:the framecomprises an opening structure that extends around the perimeter of thetrap opening; and the hood means comprises first and second attachmentmeans for attaching the hood means to the opening structure of theframe.
 3. An apparatus as recited in claim 1, further comprising:afunnel through which crabs must pass to reach the trap opening; andfixing means for fixing the hood means relative to the funnel.
 4. Anapparatus as recited in claim 2, further comprising:a funnel throughwhich crabs must pass to reach the trap opening; and fixing means forfixing the hood means relative to the funnel.
 5. An apparatus as recitedin claim 4, in which the funnel is formed from web material adapted toprevent passage of crabs therethrough.
 6. An apparatus as recited inclaim 1, in which the frame material is web material.
 7. An apparatus asrecited in claim 1, in which:the first portion of the trigger structurecomprises first and second trigger members that rotate about therotation axis; the second portion of the trigger structure comprises acounterweight member that is connected to the trigger members such thatgravity acts on the counterweight member to bias the trigger structureinto the closed position, where rotation of the trigger members aboutthe rotation axis causes the counterweight member to rotate about therotation axis; and the hood means comprises a hood structure adapted toextend over the counterweight member in a manner that allows thecounterweight member to rotate about the rotation axis.
 8. An apparatusas recited in claim 7, in which the frame comprises an opening memberdefining the trap opening and the trigger structure comprises a triggerwire that engages the opening member and has:two end portions that formthe first and second trigger members of the trigger structure; and amiddle portion that forms the counterweight member of the triggerstructure; wherein the hood structure that extends over the middleportion of the trigger wire.
 9. An apparatus as recited in claim 8, inwhich the hood structure engages the trigger wire in a manner thatinhibits movement of the trigger wire along the rotation axis.
 10. Anapparatus as recited in claim 1, further comprising stirrup meansarranged adjacent to the trap opening for inhibiting the ability ofcrabs to interfere with movement of the first portion of the triggerstructure.
 11. An apparatus for trapping crabs, comprising:a framecomprising a peripheral structure; frame material arranged on the frameto define an interior chamber, the frame material being adapted toprevent passage of crabs therethrough; at least one trap opening in theframe material through which crabs may pass; a trigger structurearranged to rotate about a rotation axis between a closed position andan open position, where the trigger structure prevents passage of crabsfrom the interior chamber through the trap opening when in the closedposition and allows passage of crabs through the trap opening when inthe open position, the trigger structure having a first portion arrangedto span the trap opening when the trigger structure is in the closedposition and a second portion that acts on the first portion to bias thetrigger structure into the closed position; and stirrup means arrangedadjacent to the trap opening for inhibiting the ability of crabs tointerfere with movement of the first portion of the trigger structure.12. An apparatus as recited in claim 11, in which:the frame comprises anopening structure that extends around the perimeter of the trap opening;and the stirrup means comprises a plurality of attachment means forattaching the stirrup means to the opening structure of the frame. 13.An apparatus as recited in claim 11, further comprising:a funnel throughwhich crabs must pass to reach the trap opening; and fixing means forfixing the hood means relative to the funnel.
 14. An apparatus asrecited in claim 11, in which:the frame comprises an opening structurethat extends around the perimeter of the trap opening, the openingstructure having an upper portion substantially coextensive with therotation axis and a lower portion; the first portion of the triggerstructure comprises a plurality of trigger members, where lower ends ofthe trigger members extend below the lower portion of the openingstructure; and the stirrup means comprises a stirrup structure for eachof the trigger members, where each stirrup structure is arranged toreceive the lower ends of the trigger members in a manner that allowsthe trigger structure to rotate between the open and closed position butreduces the ability of crabs within the interior chamber to rotate thetrigger structure from the closed position into the open position. 15.An apparatus as recited in claim 14, in which:the trigger members rotatein a first direction when the trigger structure moves from the closedposition and into the open position and in a second direction oppositeto the first direction when the trigger structure moves from openposition into the closed position; and each stirrup structure isconfigured and arranged within the interior chamber to prevent crabswithin the interior chamber from rotating the trigger members in thefirst direction while allowing crabs entering the interior chamberthrough the trap opening to rotate the trigger members in the firstdirection.
 16. An apparatus as recited in claim 11, in which:the firstportion of the trigger structure comprises a plurality of triggermembers each having a lower end; and the stirrup means engages the lowerends of the trigger members when the trigger structure is in the closedposition in a manner that prevents movement of these ends along aspreading axis substantially parallel to the rotation axis.
 17. A methodof trapping crabs comprising the steps of:providing a crab pot having atrap opening through which crabs may pass; arranging a trigger structureon the crab pot adjacent to the trap opening such that the triggerstructure rotates about a rotation axis between an open position inwhich crabs may pass through the trap opening and a closed position inwhich the trigger structure inhibits passage of crabs through the trapopening; attaching a protection structure to the crab pot adjacent tothe trap opening such that the protection structure reduces thelikelihood that crabs within the pot will (a) interfere with movement ofthe trigger structure between the open and closed positions and (b)cause the trigger structure to rotate into the open position.
 18. Amethod as recited in claim 17, in which:the trigger structure comprisesa counterweight portion arranged above the trap opening to bias thetrigger Structure into the closed position; and the protection structurecomprises a hood extending over the counterweight portion of the triggerstructure, where the hood substantially prevents crabs from interferingwith movement of the counterweight portion of the trigger structure. 19.A method as recited in claim 17, in which:the trigger structurecomprises a plurality of trigger wires arranged to span the trap openingwhen the trigger structure is in the closed position; and the protectionstructure comprises a plurality of stirrups that receive lower ends ofthe trigger wires, where the stirrups substantially prevent crabs withinthe pot from causing the trigger wires to rotate into the open position.20. An apparatus for trapping crabs comprising:a crab pot having a trapopening through which crabs may pass; a trigger structure arranged onthe crab pot adjacent to the trap opening such that the triggerstructure rotates about a rotation axis between an open position inwhich crabs may pass through the trap opening and a closed position inwhich the trigger structure inhibits passage of crabs through the trapopening; a protection structure attached to the crab pot adjacent to thetrap opening such that the protection structure reduces the likelihoodthat crabs within the pot will (a) interfere with movement of thetrigger structure between the open and closed positions and (b) causethe trigger structure to rotate into the open position.